94 REPTILES AND BIRDS. 



always) of the back and sides are quincuncial, rounded, and im- 

 bricate ; the tongue is narrow, short, flat, and but slightly forked ; 

 and the head is of a conical shape, and is covered with regular 

 shields. 



Of the families thus characterised, some only have distinct eyelids, 

 as the families Acontiadce, Ophiomoridce, Sepsidce, and Scincidce ; 

 while others have the eyelids rudimentary and the eyes exposed, as 

 the families Lialisidce, Aprasiadce, Pygopodidce, and Gymnopthahnidce. 

 In the Acontiadce the nostrils are placed in the enlarged rostral plate, 

 with a longitudinal slit behind. The form of the body much 

 resembles that of our common Orvet, or Blind- worm, and their limbs, 

 when present, are so rudimentary that they can aid little in locomotion. 

 One genus, Acontias, is without limbs, and the eyes are furnished with 

 a lower lid, while the upper eyelid is rudimentary. Of this, one 

 species, A. meleagris, inhabits South Africa ; and another, A . Layardii, 

 has been discovered in Ceylon. The genus Nessia has four rudi- 

 mentary limbs, and the rostral shield is large, sub-conical, and de- 

 pressed. In one species, N. monodactyla, the limbs are diminutive, the 

 posterior placed far apart from the anterior, all being very short, weak, 

 and undivided into toes. In another, N. Burtoni, each foot is 

 divided into three minute toes. Both species are peculiar (so far as 

 known) to Ceylon, and the habits of this family are much the same 

 as those of our common Orvet (Anguis fragilis). 



The family of Ophioi?ioridce is founded on a single genus and 

 species, Ophiomorus miliaris, which inhabits North Africa. As re- 

 marked by Dr. Gray, this reptile seems to be intermediate to the 

 Acontiadce and the Scincidce, and makes it appear as if the large 

 rostral shield of the former was formed of the united rostral, supra- 

 nasal, and nasal shields of the present family, and of the Scincidcz. It 

 has an elongate, cylindrical body, without external limbs, and the 

 ears are hidden under the skin ; the eyes are distinct, with valvular 

 eyelid ; and the scales of the body and somewhat elongate tail are 

 hexagonal. 



The Sepsidce differ from the preceding, and also from the great 

 family of the Scincidce, by having the nostrils placed in the front 

 edge of a small shield, in a notch at the hinder side of the rostral 

 plate, which latter is rather large and square. The eyes are dis- 

 tinct, the lower eyelid scaly, or with a transparent disc ; body 

 fusiform or sub-cylindrical, elongate. These reptiles burrow in dry 

 sand, and are peculiar to the anciently-known continents and certain 

 islands. Some have a wedge-shaped head, with prominent rostral 

 plate. Of these the genus Sphenops has more developed limbs, 



